Heat and Mass Transfer The unit of overall coefficient of heat transfer is kcal/m² hr °C kcal/hr °C kcal/m² kcal/m hr °C kcal/m² hr °C kcal/hr °C kcal/m² kcal/m hr °C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In counter current flow heat exchanger, the logarithmic temperature difference between the fluids is ________ as compared to parallel flow heat exchanger. Same None of these Less Greater Same None of these Less Greater ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer An electric cable of aluminium conductor (k = 240 W/mK) is to be insulated with rubber (k = 0.15 W/mK). The cable is to be located in air (h = 6 W/m²). The critical thickness of insulation will be 800 mm 25 mm 40 mm 160 mm 800 mm 25 mm 40 mm 160 mm ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According of Kirchhoff's law Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Emissive power and absorptivity are constant for all bodies Radiant heat is proportional to fourth power of absolute temperature Emissive power depends on temperature Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Emissive power and absorptivity are constant for all bodies Radiant heat is proportional to fourth power of absolute temperature Emissive power depends on temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer If the temperature of a solid surface changes form 27°C to 627°C, then its emissive power changes in the ratio of 9 81 3 270 9 81 3 270 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Stefan Boltzmann law, the total radiation from a black body per second per unit area is directly proportional to the Square of the absolute temperature Fourth power of the absolute temperature Cube of the absolute temperature Absolute temperature Square of the absolute temperature Fourth power of the absolute temperature Cube of the absolute temperature Absolute temperature ANSWER DOWNLOAD EXAMIANS APP